Recent content by selseg

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    Electroplating Cu on Cu sputtered Si Substrate (Lithography)

    I have been trying to plate Copper on Copper sputtered Electronic grade Silicon Substrate which has been patterned and developed using UV photolithography. The patterns measure about 50-100microns in width and are about 1600microns long. I have tried plating 10micrometer thick Cu using a stock...
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    How can I plate Cu at very low currents

    Hello, I have a silicon wafer with a 50nm layer of copper sputtered on it. I coated it with a 1µm of positive photo resist and patterned it with a UV laser stepper. Then I developed it and washed it thoroughly. The pattern has a surface area which measures appx 1300µm x 8µm. What I want to do...
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    Interpretation of chromatogram

    1. In my polychemistry laboratory , the task was to determine the Number Average Molecular Weight and the Weight Average Molecular weight of two samples , one a polystyrene sample prepared by radical polymerization , and the other a polystyrene-block-isoprene polymer prepared by anionic...
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    How to draw tangent from point of inflection on a chart with peaks

    I can , I thought it should look very professional.Sometimes I can't help thinking that way , thanks for drawing my attention to 'common sense' Its a chromatogram
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    How to draw tangent from point of inflection on a chart with peaks

    Hi , I have an assignment which requires that I draw tangents from the point of inflection on a peak to the x-axis.I still cannot figure out how to do that using qtiplot or excel.
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    Pickling of steel in Hydrochloric Acid

    I have some pieces of rusted mild steel pipes that i intend to remove rust from.I inserted a test sample in 15% Hydrochloric acid for 4 hours after which all the rust was removed from the surface and corrosion has slowed dramatically after washing off the acid.The subsequent pieces of steel pipe...
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    Diffnt suppliers, same composition (AlTiB) yielding 2 different Grains

    Thank you very much Alkim ,I will do just that
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    Diffnt suppliers, same composition (AlTiB) yielding 2 different Grains

    Thank you very much Alkim ,It makes a lot of sense. But still on the first question , below are the results from the two samples .less than 0.3% of the composition is not accounted for from the analysis .Is that enough impurity to make such a huge difference ? Al --88.441 --89.443 Si...
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    Diffnt suppliers, same composition (AlTiB) yielding 2 different Grains

    I work at an Aluminum sheet casting plant, we use AlTiB as the grain refiner for our cast products.Ti:B ratio as indicated on certificates is 5:1 .We recently received a new consignment of AlTiB from another supplier in India.The certificates from our new supplier show that the The AlTiB we...
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    Which electrolyte can I use for electrolytic etching of Aluminium

    Which Electrolyte can I use to etch Aluminum without generating toxic gases , I currently use 1200ml Water, 1200ml (30%-33% HCl) , 1200ml(68% HNO3) , 80ml(50% HF)
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    Simple Circuit for high power LED

    Thank you very much , I checked from the link below earlier on . Why do they include the LM317 in that circuit ? in another circuit i found online , they used l7805. Why do they include these ics and capacitor ? http://www.instructables.com/id/Super-simple-high-power-LED-driver/?ALLSTEPS
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    Simple Circuit for high power LED

    What simple circuit that I can design for a 3V high power LED with max current 0.8 amps , I think the component names would help me , I would like to power it on 4.5 to 9 V batteries .Preferably lower voltages. Thanks
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    Fly Colliding with Car/Plane at 100/800km/hr

    This is not a homework question anyway its just one of those questions that keeps occurring to me but it seems I forgot Newtons first law of motion . Thanks
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    Fly Colliding with Car/Plane at 100/800km/hr

    Assuming a car is traveling at 100km/hr and there is a fly on the dashboard of the car, if the housefly attempts to fly , would it collide with the back glass of the car or it would move with the same velocity as the car thus being stationary. Assuming the same situation in a plane traveling...
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    Materials Engineering Final Year Project Ideas

    Does anyone know any challenging Materials engineering related project I could undertake , I am in my final year and I would want a challenging final year project, preferably in industry.
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